Frozen pie products prepared by the conventional methods are obtained by wrapping a roll-in fat in a dough, repeatedly folding the dough to give a pie dough wherein dough layers and fat layers are laminated alternately, and wrapping a filling, etc. in this pie dough. When such a frozen pie dough product is baked in an oven (in particular, a high-power oven at a high temperature in a short time) directly from the frozen state, heat transfers quickly in the periphery of the dough but slowly in the inside. Thus, the inside starts to puff after the baking and hardening of the periphery has considerably proceeded. As a result, the baked pie has a non-uniform shape. Since heat can only insufficiently transfer toward the inside, moreover, there arise some problems such that the pie is half-baked in some parts and has a less crispy and poor texture.
To overcome these problems, it has been a practice to thaw a frozen dough before cooking or to bake at a low temperature over a long period of time when a frozen dough is baked as such.
To obtain a pie product of certain qualities by thawing a frozen dough product, the thawing temperature and time should be sufficiently controlled. In addition, it takes a long time for thawing. That is to say, a lot of labor and skill are needed therefor. On the other hand, it takes a considerably long time to bake a frozen pie dough product at a low temperature. Accordingly, there arises a problem in this case that baking cannot be conveniently performed anytime needed. It is impossible to obtain a final product having a favorable and well risen layered structure and a crispy texture inherent to pie by baking the conventional frozen pie dough products directly in a frozen state by using a high-power oven. It is an object of the invention to solve these problems.